Springtails

Springtails are small,jumpy arthropods that are similar to insects.When dis-turbed,they use a forked structure on the bottom of the abdomen to jump 3/4-2 inches.They are common and abundant in the litter layer of natural ecosystems. In greenhouses, a few species cause problems occasionally on seedlings and young plants.They are unlikely to be a problem for plants grown in a soilless medium.

Damage

Springtails feed on decaying matter, algae,and fungi and are normally only a nuisance. Some species, however, will feed on living plants.They chew pinholes in seedlings and young plants or scrape their foliage. Springtails may also feed on roots, causing plants to wilt and increasing susceptibility to plant pathogens.

Description and life cycle

Springtails are small and wingless.They vary in color, but most are white. Females lay up to 120 smooth, spherical, cream-colored eggs in small groups in the soil.The immatures resemble the adults but are smaller.They grow through six to eight instars (depending on the species) in about 11/2 months and attain sexual maturity before they reach maximum size. Springtails tend to mass together in enormous numbers.

Monitoring

Large populations of springtails may be visible on the soil surface.They can also be detected by floating the soil or submerging potted plants in a bucket of water.The springtails will come out of the soil and be visible on the surface of the water.

Natural enemies

Many natural enemies attack springtails in natural ecosystems. Most are opportunistic general predators, but a few are specific to springtails or have been observed attacking springtails in greenhouses.

Predators

Hypoaspis (=Geolaelaps) spp.These tiny mites feed upon small, soil inhabiting insects, mites, and all stages of springtails.They are aggressive predators, consuming 15-30 prey daily, killing more small prey than large prey. H.miles and a Geolaelaps sp.are offered commercially, although little is known about their ability to control springtails in greenhouses.

Other predators. It is hard for active predators to catch springtails because they jump when they are touched. However, three genera of ground beetles from the Northern Hemisphere (Loricera, Leistus, and Notiophilus) feed specifically on springtails. Some other arthropods, such as spiders, mites, and pseudoscorpi-ons,are known springtail predators.

A grower in Finland found that numerous Pardosa amentata spiders were living on springtails which were very abundant in the peat used as a growing substrate for the lettuce crop in the greenhouse.

None of these predators is commercially available or has been investigated for use in greenhouses.

Pathogens

The nematodes Steinernema feltiae (=Neoaplectana bibionis) and Heterorhabditis bacteriophora (=helioth-idis) infected one species of springtail in laboratory experiments. Because spring-tails live in the soil, there is good potential for nematodes to infect them.These nematodes are commercially available. (See "Fungus Gnats and Shore Flies" or "Weevils" for more information on nematodes.)

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